The 36-year-old singer took to Instagram on Thursday night (30Mar17) to share the exciting news, posting a picture of the baby scan alongside the book Your Pregnancy Bible.
"Look at what wifie (sic) is reading again!" he wrote alongside the picture. "Here we go again #jodialbert baby no.3 is on the way!!!"
Jodi, 33, then shared the same picture on her own Instagram account, writing: "Looks like I might be needing this again... baby no3 (sic)."
The baby news comes after Jodi previously revealed that she and Kian were keen to have "three or four children" eventually.
"Kian is from a big family of seven, so ideally we'd like three or four," she told OK! magazine. "The Irish have big families. We'd love a girl, but so long as they were happy and healthy, that's all that really matters."
Kian and former Hollyoaks actress Jodi are already parents to sons Koa, five, and 22-month-old Zeke. The couple wed in Barbados in 2009 after a five-year romance.